Joel,
It ain't over until it's over. The statewide effort will not limit transformerless inverters if I have anything to do with it. This is something these guys got on their brain, and they won't let it go-YET. Once they understand better that these inverters are safer, we will get them to back down. Bill. From: [email protected] [mailto:[email protected]] On Behalf Of Joel Davidson Sent: Thursday, April 19, 2012 6:47 PM To: RE-wrenches Subject: Re: [RE-wrenches] Transformerless inverters A Los Angeles contractor replied off-list that transformerless inverters cannot get permitted through LA Department of Building & Safety's new express permit process that uses boilerplate drawings. They can get permitted through regular plan check. This would not be an issue, but LADWP and the LA Department of Building & Safety are very influential nationally. They have teamed up to spearhead a statewide effort to standardize system designs to expedite permitting PV systems under 10 kW. Other utilities have their eyes on what LADWP is doing. Joel Davidson ----- Original Message ----- From: William Korthof <mailto:[email protected]> To: [email protected] Sent: Wednesday, April 18, 2012 11:44 PM Subject: Re: [RE-wrenches] RE-wrenches Digest, Vol 5, Issue 113 Interesting update.... I've installed dozens of non-isolated transformerless inverters with LADWP customers since those genius inverters first became available from Power-One's inverter ancestor, Magnetek. I don't remember ever having a conflict or technical issue with an engineer or inspector questioning the suitability of that class of inverter, or even looking for the double-insulated solar wire that is supposed to be required for the exposed solar wires. /wk On 4/16/2012 9:05 AM, Joel Davidson wrote: Wrenches, Los Angeles Department of Water & Power (LADWP), the largest and most influential municipal utility in the US is finally going to allow transformerless inverters for residential PV systems. Are there any design, installation or reliability issues to consider with the SMA and other high-frequency transformerless inverters. Can they be mounted on a hot south or west wall or do the have to be kept cool in the shade? Joel Davidson
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